A heavy metal containing waste water refers to industrial waste water and urban sewage water which contain iron, copper, zinc, mercury, lead, cadmium, chrome, arsenic, aluminum and the like.
The conventional waste water treating method is such that metals are treated as hydrates in accordance with the solubility under the optimum pH state. However, if various metals exist in a mixed form within the waste water, they cannot be simply treated. Therefore, there is required a method which is capable of treating all the metals at the same time.